Fructosamine is a general term that applies to any glycated protein. In vivo, glucose can combine with the amine group of some proteins in a non- enzymatic reaction to form intermediate compounds called aldimines. Aldimines are not very stable and may dissociate or undergo an Amadori rearrangement to form stable compounds called fructosamines. The formation of glycated proteins is normal and occurs at a low rate in non-diabetics. High blood sugar favors the formation of stable fructosamine. Fructosamine detects the level of glycemic control over a period of 2-3 weeks as it is based on the half-life of serum proteins as albumin. In comparison, glycated hemoglobin values (HbA_1c) detect glycemic control over 6-8 weeks, which correlates with the half life of hemoglobin. Fructosamine is particularly helpful in distinguishing excited, temporarily hyperglycemic cats from diabetic cats from diabetic cats.

Electrolytes (March 1998)

Electrolyte WARNING: Over-heparinizing samples for electrolyte determinations will significantly alter results:

Heparin syringe* Hitachi serum

Na 152 147

K 2.6 4.4

I-Ca 0.78 15.9 (total calcium)

Smooth-E syringe** Heparin syringe^

Na 145 146

K 4.6 4.1

I-Ca 2.04 2.15

Plasma from the Heparinized syringe* and Hitachi serum were repeated on the Hitachi and ABL505, respectively. Results matched original values; the problem was not due to instrument malfunction.

*Heparin syringe: original draw of < 1 ml with “just a little bit of heparin left the syringe”.

**Smooth-E syringe: redraw using a “balanced lyophilized heparin” designed to minimize the negative effects of heparin.

^Heparin syringe: redraw of 4 ml blood and expelled all heparin from the syringe.

Remember your results are only as good as the sample submitted! Expel all heparin from the syringe and collect at least 1 ml of blood; the more volume the more accurate the results. We have a supply of Smooth-E syringes for those wishing to submit samples collected by both means for a comparison study. The second sample will be run at no charge to the client. You may want to use a larger needle than that supplied with the Smooth-E syringe. It’s only a 23 gauge needle!

CE: The Influence of Monoclonal Immunoglobulin on Serum Phosphorous: (June 2002)

The automated method used by CSU-VTH Clinical Pathology for the assay of inorganic phosphorous can lead to erroneous results in the presence of monoclonal immunoglobulins. Falsely elevated results are caused by the precipitation of the monoclonal immunoglobulins in the reagent-sample mixture.

Multiple myeloma is the most common cause of monoclonal gammopathy in small animal patients, but still remains an uncommon diagnosis. It is predominately found in dogs, and is rare in cats and horses. Multiple myeloma is a tumor of more mature plasma cells, which typically secrete IgG and IgA in relatively equal proportions. IgG is the predominant immunoglobulin in cases occurring in cats. Other causes of monoclonal immunoglobulins can be canine ehrlichiosis, feline infectious peritonitis (FIP), chronic pyoderma, leishmaniasis, amyloidosis, and plasmacytic gastroenteritis.

References:

Bakker A., Bosma H., Christin P. Influence of monoclonal immunoglobins in three different methods for inorganic phosphorus. Ann Clin Biochem 1990; 27:227-231.

Feldman, B., Jain, N., Zinkl, J., Schalm’s Veterinary Hematology, 5^th Edition, 2000.